Low luminosity Type II supernovae - IV. SN 2020cxd and SN 2021aai, at the edges of the sub-luminous supernovae class

Photometric and spectroscopic data for two Low Luminosity Type IIP Supernovae (LL SNe IIP) 2020cxd and 2021aai are presented. SN 2020cxd was discovered 2 d after explosion at an absolute magnitude of Mr = -14.02 ± 0.21 mag, subsequently settling on a plateau which lasts for ∼120 d. Through the luminosity of the late light curve tail, we infer a synthesized 56Ni mass of (1.8 ± 0.5) × 10-3 M⊙. During the early evolutionary phases, optical spectra show a blue continuum ($T\, \gt$8000 K) with broad Balmer lines displaying a P Cygni profile, while at later phases, Ca ii, Fe ii, Sc ii, and Ba ii lines dominate the spectra. Hydrodynamical modelling of the observables yields $R\, \simeq$ 575 R⊙ for the progenitor star, with Mej = 7.5 M⊙ and $E\, \simeq$ 0.097 foe emitted during the explosion. This low-energy event originating from a low-mass progenitor star is compatible with both the explosion of a red supergiant (RSG) star and with an Electron Capture Supernova arising from a super asymptotic giant branch star. SN 2021aai reaches a maximum luminosity of Mr = -16.57 ± 0.23 mag (correcting for AV = 1.92 mag), at the end of its remarkably long plateau (∼140 d). The estimated 56Ni mass is (1.4 ± 0.5) × 10-2 M⊙. The expansion velocities are compatible with those of other LL SNe IIP (few 103 km s-1). The physical parameters obtained through hydrodynamical modelling are $R\, \simeq$ 575 R⊙, Mej = 15.5 M⊙, and E = 0.4 foe. SN 2021aai is therefore interpreted as the explosion of an RSG, with properties that bridge the class of LL SNe IIP with standard SN IIP events.GV acknowledges INAF for funding his PhD fellowship within the PhD School in Astronomy at the University of Padova. MLP acknowledges support from the plan ‘programma ricerca di ateneo UNICT 2020-22 linea 2” of the University of Catania. AR acknowledges support from ANID BECAS/DOCTORADO NACIONAL 21202412. NER acknowledges partial support from MIUR, PRIN 2017 (grant 20179ZF5KS), from the Spanish MICINN grant PID2019-108709GB-I00 and FEDER funds, and from the programme Unidad de Excelencia María de Maeztu CEX2020-001058-M. LG acknowledges financial support from the Spanish Ministerio de Ciencia e Innovación (MCIN), the Agencia Estatal de Investigación (AEI) 10.13039/501100011033, and the European Social Fund (ESF) ‘Investing in your future’ under the 2019 Ramón y Cajal programme RYC2019-027683-I and the PID2020-115253GA-I00 HOSTFLOWS project, from Centro Superior de Investigaciones Científicas (CSIC) under the PIE project 20215AT016, and the programme Unidad de Excelencia María de Maeztu CEX2020-001058-M. TMB acknowledges financial support from the Spanish Ministerio de Ciencia e Innovación (MCIN), the Agencia Estatal de Investigación (AEI) 10.13039/501100011033 under the PID2020-115253GA-I00 HOSTFLOWS project, and from Centro Superior de Investigaciones Científicas (CSIC) under the PIE project 20215AT016, and the programme Unidad de Excelencia María de Maeztu CEX2020-001058-M. Y-ZC is funded by China Postdoctoral Science Foundation (grant no. 2021M691821

Study of infestation of dogs with Echinococcus granulosus in the province of La Rioja, Argentina

Fil: Amaya, Juan C. Programa de Zoonosis, La Rioja; Argentina.Fil: Moreno, Nancy. Departamento de Investigaciones del Instituto Universitario de Ciencias de la Salud, Fundación Barceló; Argentina.Fil: Salmaso, Nancy. Laboratorio Bioquímico de Serología, Hospital Enrique Vera Barros; Argentina.Fil: Bazan, Eduardo. Laboratorio Bioquímico de Serología, Hospital Enrique Vera Barros, La Rioja; Argentina.Fil: Ricoy, Gerardo. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Parasitología; Argentina.Fil: Córdoba, Patricia. Dirección de Epidemiología del Ministerio de Salud Pública, La Rioja; Argentina.Fil: Santillán, Graciela I. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Parasitología; Argentina.This work was conducted in the province of La Rioja, located in northwestern Argentina. The aim of this study was to estimate the percentage of dog feces showing the presence of antigens of Echinococcus sp. in different regions of the province. A total of 269 samples of dried canine stool were taken, which were analyzed by the copro-ELISA technique. The most affected area was zone IV, which had 30.5% of positive samples. Zone I corresponding to the Capital Department of the province had 12% of positivity. In other areas, the percentages ranged between 11.4% and 14.8%. This is the first study in the province of La Rioja on the existence of this disease in dogs. The lack of control strategies has allowed the spread of echinococcosis